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Month: October 2016

This week at the Wonderful World of Weed Man we will be continuing on our “Your Lawn May Have the Sniffles!” lawn disease series. Last week we talked about powdery mildew. It is common this time of year, so if you are seeing it, check out that article to see how best to treat it. Today, we are going to focus on fighting blight!

As lawn fungus goes, blight can be a catchall term for many variations of leaf blight. We see a few of the variations every year. Particularly Pythium Leaf Blight as well as Ascochyta Leaf Blight. I know, I know, that is a mouthful. For today’s purposes we are going to discuss Ascochyta Leaf Blight. If you are interested in Pythium Leaf Blight, we have a great resource on our website about it.

We tend to see Ascochyta Leaf Blight most often in the beginning of summer when temps spike, or at tail end of the summer when it cools down, but we get a warm spell. The symptoms develop more commonly during hot, droughty periods that were preceded by cool, rainy conditions. As most lawn diseases this leaf blight is just another type of fungi that lives in the soil thatch year-round and develops when conditions are just right for it to thrive.

When the leaf blight shows up on the lawn, it looks very much like your lawn is dying. If you don’t know what to look for you might think that your lawn was ‘burned’ or ‘bleached’. The leaf blade of the grass will turn straw colored very quickly. The overall appearance of the lawn (in the affected areas) will look like its drought stressed or dead.

Leaf blight, in comparison to drought stress or a dying lawn, can appear overnight or within a day or two. Leaf blight, fortunately is not a blight on the crown or root portion of the grass plant. It generally affects only the blade, and does not kill the crown or root of the plant. If you look carefully at the grass blade, it will be straw colored from the tip down, but will be green at the base. Because it is not damaging the crown or root, the lawn will recover on its own.

Conditions that bring on this disease can be the following

Mowing during the heat of the day seems to be one of the factors that cause this disease to become active.

It mainly affects bluegrass and it is usually on lawns that were mowed too short, or too often.

Dull Mower blades will contribute to the severity of the disease. Your lawn mower can even spread the disease around on its wheels or mower blade as it moves up and down your property. – you can see in this picture how mower wheels spread the disease around:

As stated previously this leaf blight will recover on its own within 2-3 weeks. If you want to improve the recovery time, or prevent the issue altogether you can try the following:

Reduce thatch (where fungus spores like to lay in wait) by aerating your lawn regularly. This will allow better water flow deeper into the soil.

It’s getting cold here in the Wonderful World of Weed Man! Autumn is most certainly upon us. The air and leaves are crispier, the wind is blowing, and pumpkin spice is ever present. Even though the temps have dropped, your lawn is still alive and taking in nutrients in preparation for the winter. Now is still an important time to maintain the health of your lawn.

Let us help you achieve that by continuing our series on lawn disease. We last wrote about Rust Fungus, and this week we will talk about a similar type of fungus – Powdery Mildew. They have a few similarities, including appearing as a powdery substance on your grass blades.

If you were to take a look at our website, you would find this lawn disease describes as,

“Powdery mildew is a damaging disease of blue-grasses and fescues. Periods of low light intensity and poor air circulation favor the disease. Heavily shaded areas are particularly susceptible.”

You are most likely to see powdery mildew during the spring or fall when temperatures are lower.

Powdery Mildew – even with good fertilization, mowing, and watering habits, still shows up from time to time in my lawn. When it shows up, it only shows up in one place in my lawn. The heavily shaded area on the north side of my property. It gets little sunlight, and poor air circulation due to the position of my house and the fencing attached to it.

It is a fungal disease that looks just like it sounds. It is fairly easy to identify

Grass blades look like they have been dusted with white powder like baking soda

Powdery mildew will start off as spots on the grass blade

The white spots will spread to cover most of the upper part of the grass blade

Interestingly, powdery mildew does not require much moisture to infect plants like other fungal diseases do. Poor watering habits is typically a contributing factor to lawn disease, however in this instance you could water well and still run into this disease. Powdery mildew, though typically does not, can cause damage to the lawn if it is severe enough. As the fungus covers the grass blade it will disrupt photosynthesis. As the plant weakens, it will become even more susceptible to other lawn diseases or issues.

The ‘interwebs’ are full of advice on how to deal with powdery mildew. I found a curious DIY ‘organic’ solution made from Baking Soda. I cannot professionally account for the success of such a mixture, but apparently if you mix baking soda, water, vegetable oil and dish soap you will create a concoction to combat this disease! For those of you who would like a less involved approach to resolving powdery mildew you can do as follows –

Once discovered in your lawn, there are some easy steps to clear up the disease:

Implement recommended watering habits – deep and infrequently

Keep a high mowing height to promote a healthier root system that can withstand disease better

Reduce the amount of shade by trimming trees and shrubs that contribute to the shady areas

Increase the air circulation by thinning trees and shrubs or making appropriate changes to landscaping to promote air flow in the area of concern

Provide a light application of fertilizer to help promote recovery.

Reduce thatch with core aeration

There are fungicides that can be applied to help recover, however they can be very cost prohibitive to do.

Although there are chemicals that can help control fungus in the lawn, we generally do not recommend it. There is a time and place for use of chemical treatment, but too often homeowners just want a quick fix. Many times chemical control for fungus treats the symptoms and not the underlying cause. Chemical control can get very expensive as it needs applied consistently and often to work. If you make the necessary changes to your cultural practices it will improve on its own.

If you are seeing powdery mildew in your lawn, and need some help with it, don’t hesitate to call the Weed Man! 208-888-9911 www.weedmanboise.com #wecareforyourlawn